Airplane fairings



Aug. 7, 1945. r

T. P. HALL AIRPLANE FAIBINGS Filed Nov. 8, 1944 2 Sheets-Sheet 1' I 16 I I Jaye/7702' A .7 1945 T. P. HALL I 2,381,350

AIRPLANE 'FAIRINGS" Filed Nov. 8, 1944 2 Sheets-Sheet 2 plane it is customary or which are Patented Aug. 7, 1945 UNITED STATES, PATENT OFFICE z,ss1,ssov AIBPLANEFAIBINGS Theodore 1'. Hall, San Diego, Calif., assignor to i Consolidated Vnltee Aircraf Diego, Calif., a corporation'of Delaware t Corporatiom San Application November 8, 1944, Serial No. 562,441 5 Claims. (Cl. 244-130) The present invention relatesto fairings. y

In the manufacture or fabrication of an airbalanced control surface,

nect a movable counte trailing portion of the such as a rudder, to the forwardly disposed flxed by means of hinges in' the form of hinge brackets connectedto, and project rearwards from," the fixed surface and extend into notches in the leading portion of the control surface and a pivot rod which is carried by the control surthe brackets and is disposed rearwards of the leading edge of the control surface. Duringflight surface of the airplaneextends through holes in the rear ends of v In the drawings which accompany and. form a 1 part of'this specification or disclosure and in standard practice to conin the leading portion of the control surface and a such currents and turbulences result in pronounced fluttering or buffeting ofthe control sur-' face.

The primary object of the present invention is to eliminate in connection with an airplane having a counterbalanced control surface with hinge bracket receiving notches the formation of eddy currents and turbulences adjacent the notches'whenthe surface is deflected or angularly' adjusted during a flight maneuver. This object is attained by providing fairings which are located-at the sides of the hinge brackets and serve so to'flll and streamline the notches in the leading portion of the control surfacethat when the control surface is deflected the portions or surfaces adjacent the hinge areas present a smooth or'streamline contour to the slip stream of the airplane.

Another object ,of the invention is to provide fairings for airplane hinge brackets which are attached to, and form a part of, the brackets and Other objects of the invention and the various advantages and characteristics of the present plane hinge bracket fairings willbe apparent fr a consideration of the following detailed descrip;

tion.

The invention consists more particularly defined by claims at the conclusion hereof.-

in its leading portion,

-a re spfdesigned and constructed that they effec- I tivelyjand efllciently fulilll their intended purm in the several novel fea-' "tut-es which are hereinafter set forth'and are end of the fuselage} substantially straight,

, nected to the trailing portion of the views:

- on the line 2-2 of Figure 1 and'showing m which like letters and I note corresponding parts throughout the several the construction and ement of one of the fairing-equipped hinse brackets;

Figure 3 is a perspective of the hinge bracket showninFigurez;

Figure 4 is an. enlarged horizontal section taken on the line 4-4 of Figure 1 and illustrating in fairings at the brackets so flll and streamline lea'ding portion of the rudder that when the rudder \is deflected the portions or surfaces adjacent the hinge. areas present a smooth and streamline contour to the slip stream of the airplane and hence eliminate eddy currents and turbulences adjacent the sultant fluttering or and Figure 5- is an exemplified in c a fuselage a and an empenfuselage. As shown The invention is an airplane A having here at the rear end of the in Figure. l of the drawings, the empennage comprises an ups'tanding'verticai fln a a rudder a, a horizontal stabilizer a, and a pair of elevators s. The horizontal stabilizer projects outwards in both directions from the rear end of the fuselage a and has the elevators a pivotally connected to its trailing portion, as well understood in the art. The vertical iin a is connected to, and proiects upwards from, the upper portion of the rear and has its trailing portion although forwardly bulged or arcuate in cross section. The rudder a is disposed directly behind the vertical fin and is of the counter" balanced variety. It has a control tab a at its trailing edge and is pivotally convertlcal fin by, order that it is capable a plurality of hinges i in horizontally. The cenof swingin laterally or trai and rear portions of the rudder are rearwardlfitapered and the front portion of the rudder is transversely rounded or curved.

' The hinges 6 are shown as being four in num-' ber although more or less may be employed, 'denumerals of reference desection taken: detail.

notches and 'rebuffeting of the rudder;'

- enlarged side view of the bracket that is shown in Figures 2. 8 and 4.

3oection with V pending upon the height and size of the rudder. They are spaced vertically and equidistantly apart and comprise hinge brackets I. The latter are suitably connected to, and project rearwards from, the trailing portion of the vertical fin a and each consists of a rearwardly tapered horizontally elongated boxlike housing 8, a pair of rearwardly convergent tubes 8 and a pivot member Ill. The housings 8 of the hinge brackets 'I embody substantially fiat top walls 8', substantially fiat bottom walls 8 and channel shaped side walls 8. The top and bottom walls are spaced vertically apart, as shownin Figure 3, and define with the channel shaped side walls 8 compartments H in which the pairs of tubes 9 are disposed. The top flanges oi the side walls 8 extend inwards and underlie and are welded or otherwise fixedly secured to the side margins of the top walls 8 and'the bottom flanges of the side walls extend inwards and overlie and are welded or otherwise fixedly secured to the side margins of the bottom walls 8'; The front ends of the tubes 9 project forwards of the front ends of the box-like housings 8 and are suitably secured to certain structural elements in the trailing portion of the vertical fin a The central ings by bolts l2 which extend through aligned holes in the top and bottom walls of the housings. 1

The pivot members l0 ofthe hinge brackets I are located behind the rear ends of the tubes 9 and have in the rear ends thereof vertically aligned holes l3. The front ends of the pivot members are bifurcated so as to form forwardly divergent arms Hi and these fit within the rear ends of the tubes 9. The hinge brackets 1 fit within horizontally extending notches ll in the leading portion of the rudder a". In addition to the hinge'brackets I the hinges 6 embody a ver tically extending pivot rod l5 and this is fixedly secured within the rudder a and extends loosely through the holes It in the rear ends of the pivot members ll) of the hinge brackets "I. As

shown in the drawings the pivot rod." is located adjacent the rear ends of the notches H in the leading portion of the rudder and constitutes the articulation or pivot axis of the rudder. Because of the position of the .pivot rod with respect to the leading edge of the rudder the rudder is essentially of the counterbalanced variety. The pivot rod is, however, located forwards of the vertical center line of the rudder but inwards of the leading edge of the rudder.

In order so to fill and streamline the notches ll in the leading portion of the rudder a that when the rudder is deflected in either direction to its fullest extent the pressure sides of the hinge areas present a smooth or streamline contour to the slip stream of the airplane and hence eliminate eddy currents and turbulences and resultant fluttering and buffeting of the rudder, the brackets I of the hinges 8 are provided on the port or left hand sides thereof with fairings l8 and on their starboard or right hand sides with fairings l1. These fairings are preferably formed of sheet metal although it is to be understood that they may be'formed of other material. They are complemental as best shown in Figure 3 and are disposed adjacent and outwards of the side walls 8 of the hinge bracket housings 8.

The fairings l6 are channel shaped in cross section and consist of vertically extending walls I8, integral inwardly extending top walls l8 and integral inwardly extending bottom walls l6. They are coextensive so far as the adjacent or opposed side walls 8 are'concerned and serve to reeni'orce or strengthen the hinge brackets I as a whole. The inner margins of the top walls l8 of the fairings l8 overlie and are welded or otherwise fixedly secured to the adjacent side margins of the top walls 8 of the housings 8 and the inner margins of the bottom walls I8 underlie and are welded or otherwise fixedly secured to the adjacent side margins of the bottom walls 8 of the housings 8. The vertically extending walls l8 are spaced outwards from the adjacent side walls 8 of the housings and are horizontally curved in such manner that when the rudder a, is swung substantially to its fullest extent in a counterclockwise direction as viewed in Figures 1 and 4, it is substantially coplanar with the left hand side of the leading portion of the rudder and hence fills and streamlines the pressure sides of the notches ll. As shown in the drawings the top and bottom walls I8 and I6 of the fairings l8 are spaced apart a distance slightly less than the height of the notches H with the result that when the rudder is swung or turned in a counterclockwise direction to' substantially its fullest extent the fairings l8 eifect filling and sealing of the pressure sides of the notches.

The fairings I! are channel shaped in cross section and consist of vertically extending walls I1", integral inwardly extending top walls li and integral inwardly extending bottom walls I7.

They are coextensive with the adjacent or opposed side walls 8 of the housings 8 and serve,

like the fairings I8, to reenforce or strengthen,

the hinge brackets I as a whole. The inner margins of the top walls ll of the fairings ll overlie and are welded or otherwise fixedly secured to the adjacent side margins of'the top walls 8 of the housings 8 and the inner margins of the bottom walls I! underlie and are welded or otherwise fixedly secured to the adjacent side margins of the bottom walls 8 The vertically extending walls ll are spaced outwards of the adjacent side walls 8 of the housings and are horizontally curved in such manner that when the rudder a is swung substantially to its fullest extent in a clockwise direction as viewed in Figures 1 and 4, it is substantially coplanar with the right hand side of the leading portion of the rudder and hence fills and streamlines the pressure sides of thenotches ll. As shown in the drawings the top and bottom walls I'I and 11 of the fairings I! are spaced apart the same distance as the top and bottom walls I8 and I6 of the fairings l8 with the result that when' the rudder is swung or turned in a, clockwise direction substantially to its fullest extent the fairings l1 efi'ect filling 7:111 sealing of the pressure sides of the notches The rear ends of the vertically extending walls of the fairings l8 and H are curved inwards to agradual extent in the direction of the pivot members I 9 ofthe housings 8 of the hinge pressure areas of the notches together with resultant fluttering and buifeting of the rudder are avoided or eliminated. When the rudder a in connection with flight of the airplane A is swung by the pilot to its fullest extent in a clockwise direction the fairings H are brought into play and serve to fill and streamline the pressure sides of the notches M with the result that the hinge areas present a smooth or streamline contour to the slip stream.

The herein described fairings efiectively and They efliciently fulfill their intended purpose.

are light in weight and may be applied to the hing brackets l with facility.

Whereas the fairings have beenvspecifically described in connection with hinge brackets for.

a counter-balanced rudder it is to be understood that they may be used in connection With'hinge brackets for other areo-dynamic control surfaces, such, for example, as ailerons, elevators, flaps and control surface tabs. It is also to be understood that the invention is not to be restricted to the details set forth since'these may 1. In an airplane having a fixed surface with vrearwardly projecting hinge brackets along as trailing portion andin addition a control surface positioned behind the fixed surface, embodying notches in its leading portion'for the hinge brackets and provided with pivot means between it and the rear ends of the brackets,

fairings.disposedadjacent'the sides of the hinge brackets and adapted and arranged to fill and streamline the pressure sides of the notches when the control surface is deflected or pivoted in either direction to substantially its fullest extent in connection with a flight maneuver.

2. In an airplanehaving a fixed surface with rearwardly projecting hinge brackets along its trailing portion andin addition a control surface positioned behind the fixed surface, em-

bodying notches in its leading portion for the hinge brackets and provided with pivot means between it and the rear ends of the brackets,

pairs of fixedly mounted fairings associated re-' spectively with, and positioned on opposite sides of, the hinge brackets and adaptedand arranged to fill and streamline the pressure sides of the notches when the control surface is deflectedor pivoted in either direction to substantially its fullest extent in connection with a flight ma neuver.

3. In an airplane having a fixed surface with rearwardly projecting hinge brackets alongv its trailing portion and in addition a control surface positioned behind the fixed surface, embodying notches in it leading portion for the hinge brackets and provided with pivot means between it and the rear ends of the brackets, fairings connected to, and disposed outwards of, the sides of the hinge brackets and adapted and arranged to fill and streamlin the pressure sides of the notches when the control surface is deflected or pivoted in either direction to substan -tially its fullest extent in connection with a flight maneuver.

4. In'an airplane embodying a fixed surface with rearwardly projecting hinge brackets along its trailing portion and in addition a control surface positioned behind the fixed surface, havwardly convergent fairings associated resplectively with, and disposed adjacent and outwards of, the sides of the hinge brackets and adapted and arranged to fill'and streamline the pressure sides of the notches when the control surface is deflected or pivoted in either direction to substantially its fullest extent in connection with a flight maneuver.

5. In an airplane embodying a fixed surface with rearwardly projecting hinge brackets along its trailing portion and in addition a control surface positioned behind the fixed surface, embodying notches in its leading portion for the hinge brackets and provided with pivot means between it andthe rear ends of the brackets, channel shaped fairings disposed adjacent. and outwards of the sides of the hinge brackets, provided with inwardly extending walls in connected relation with said sides of the hinge brackets, and adapted and arranged to fill and streamline the pressure sides of the notches when thecontrol surface is deflected or pivoted in either direction to substantially its fullest extent in connection with a flight maneuver.

'IHEODORE P. HALL. 

